Shielding enclosure



Oct. 20, 1964 E. A. LINDGREN SHIELDING ENCLOSURE 2 Sheets-$heet 1 Filed Nov. 15, 1961 INVENTOR.

. ERIK A. LINDG ATT YS Oct. 20, 1964 A. LINDGREN 3,153,692

SHIELDING ENCLOSURE Filed Nov. 15, 1961 2 Sheets-Sheet 2 INVENTOR: ERIK A. LIN DGREN United States Patent 3,153,692 SHIELDING ENCLGSURE Erik A. Lindgren, 4119 N. Troy, (Ihicago, Ill. Filed Nov. 15, 1961, Ser. No. 152,547 6 Claims. {CL 174-35) This invention relates in general to the construction of electrically shielded enclosures, commonly referred to as isolation rooms, for protection from high frequency wave eminations and magnetic fields and in particular to the shielding material and interlock device for securing adjacent panels of a portable prefabricated isolation room whereby the room may be readily assembled and disassembled without loss of shielding effectiveness.

Shielding efiiciency is related to conductivity and nonpermeability and it is well known that continuous electrical conductivity between contiguous points in a shielding element affords a pronounced efficiency as a radial wave shield in the intermediate and lower wave bands. However, by utilizing multiple mutually spaced shielding enclosures, the quality of waves may be further enhanced and extended over a wider range of frequencies.

Various materials are known to possess shielding char acteristics which, to some degree, serve the purpose of isolating a space between or against electrical magnetic and electrostatic wave penetrations. In prior shielded enclosures of this type, a copper mesh screen has been conventionally used and has been considered the better effective shielding material. In construction of a double shielded isolation room, each individual shield must completely encompass the space to be shielded, one within the other, yet maintain continuity of conduction between panels with the minimum amount of hard wear and a minimum of members which might penetrate the shielding material and effect the over all effectiveness of the shielded enclosure. Further, it has been found preferable to provide a shielding member which provides a solid, rigid structure which eliminates the possibility of accidental penetration or separation from the supporting members.

In recognition of these factors and desired objects, it is p the principle object of this invention to provide an improved prefabricated multi-panel shield room construction utilizing double electrically isolated shields in which continuity of conduction between corresponding shield elements of contiguous panels is automatically established as the panels are assembled to one another while complete electric isolation of one shield from the other is maintained.

A specific object of this invention is to provide an improved connecting device for readily securing prefabricated panels of a double electrically isolated shield room yet maintaining continuity of conduction between the corresponding shield elements at all times.

Another object of this invention is to provide an improved connecting device for securing adjacent prefabricated panels of electrically isolated shield room which provides a covering member for the seam formed by the abutting edges of the adjacent panels.

Another object of this invention is to provide an improved connecting device for securing adjacent prefabri- 3,153,692 Patented Oct. 20, 1964 readily permits assembly and disassembly of the panels in close quarters without loss or injury of the continuity effectiveness.

Another specific object of this invention is to provide an improved prefabricated panel construction utilizing a thin solid sheet of shielding material secured to both sides of a dielectric material.

A further object of this invention is to provide a prefabricated panel having double spaced apart solid shield elements arranged to maintain continuity of conduction between corresponding shield elements and to provide two completely electrically isolated enclosed areas one within the other, when the panels are connected together to form the isolated room.

A further obiect of this invention is to provide an improved prefabricated double isolation panel providing two thin solid sheets of metallic material maintained in spaced apart relationship by a laminated wooden member.

Other objects and advantages of the shielded isolation room of this invention, the prefabricated panels and the interconnecting devices will appear from the follomng specifications and drawings in which:

FIG. 1 is a perspective view illustrating an isolation room made up from a plurality of one basic frame type prefabricated panel secured in position by a connecting device of this invention;

FIG. 2 is a fragmentary front perspective view of the prefabricated panel of this invention from which the isolation room is formed;

FIG. 3 is a fragmentary sectional view talren along the line f)3 of FIG. 1 illustrating the connecting of two adjacent intermediate panels;

FIG. 4 is a fragmentary sectional view taken along the lined-4- of FIG. 1 illustrating the corner connection of two panel members;

FIG. 5 is a fragmentary front perspective view illustrating the relationship of a three panel corner connection prior to the mounting of a corner connecting member; and

FIG. 6 is a fragmentary perspective view in front elevati-on, similar to that shown in FIG. 4, with the corner connecting member secured in position.

Panel Structure Referring now to FIGS. 1 and 2, the basic panel M, from which this isolation room is constructed, is preferably formed from a solid dielectric member 12 and is illustrated throughout the drawings as being formed from a three layer wooden lamination commonly referred to as plywood. The plywood member 12 has the outer surfaces totally covered by a thin layer of shielding material 16, preferably copper or steel, which is secured to the plywood 12 by any suitable bonding method. As best seen in FIG. 2, the panel member 10 provides edge surfaces 18, 20, 22 and 2.4 which are completely flat and disposed at right angles to the opposing side surfaces 26 and 28. Each of the panels required for forming the isolation room are identical in construction and configuration exthe solid metal shielding material 16 with the peripheral edge of the shielding material terminating at the juncture of the edge surfaces 13, 20, 22 and 24 with the side surfaces Ztiand 23. By providing a dielectric material such as plastic or the plywood member 12, between the sheets of metal shielding material 16, there is provided a comcated panels of electrically isolated shield room which pletely spaced apart electrical isolation of the two shields which when connected to similar panels in continuous relationshipprovide continuity of electrical conduction between the several shielded elements.

"h (D Intermediate Panel Connecting Device Referring now to FIG. 3, the connecting device for joining the adjacent panels ltl, indicated generally by the numeral 29, is secured to the adjacent panels from both sides and provides an overlapping member which not only secures the two panels in tight rigid relationship and automatically maintains conduction of adjacent shields, but provides a cover for the seam formed by the abutting edges.

The connecting device 29 provides a metallic strip 30 disposed on both sides of the panels 19 to lie over the seam formed by the abutting edges of the adjacent panels. At spaced intervals along the entire length of the panel, an insert 32, preferably formed from a dielectric such as plastic, is positioned between the adjacent panels to abut against the inner surfaces of the two strip members 3%. A holding screw 3 is positioned centrally through each of the strips 3th to engage the ends of the insert member 32. To insure the two adjacent panels are held tightly together, a hold down screw 36 passes through one end of each strip 30 and into a panel 1% adjacent the end thereof with the screw members 36 being embedded in adjacent panels on opposite sides as shown. Thus, it is readily understood that by mounting the strip members 36 to panels lit at time of manufacturing of the panels, final assembly of the isolation room will only require the insertion of the inserts 32 and embedding of the opposing screw members 34.

Two Panel Corner Connection Referring now to FIG. 4, a two panel corner juncture of the isolation room is illustrated as being secured in essentially the same manner as the adjacent intermediate panels lb described above. A right angle member 38 is prefabricated, in similar manner as the panels 1t), and provides a center portion 49, formed from a dielectric material such as laminated plywood, with the outer surfaces covered by a shielding material 42, similar to that utilized on the panels Ill. Each of the abutting panel members iii are connected to the right angle member 38 in identical manner as the abutting intermediate panels. A plastic insert member 32 is disposed between the panel members it and the right angle member 3% at spaced intervals along the length of the seam with the overlapping metallic strip members 35 being secured to the panel in and the right angle member 33 by the screw members 36 and to the plastic insert by the screw members 34.

Three Panel Corner Connection Referring now primarily to FIGS. and 6, one of the eight corner junctions of three panels of an isolation room is illustrated in perspective with the two panel corner connections, previously described, being partially shown. As best seen in FIG. 5, the strip members 3% terminate a substantial distance from the ends of the panel members lit) and right angle members 38 for receipt of a portion of a metallic cover strip on a corner connecting member as will now be explained.

A corner connector member, indicated generally by the numeral 44, provides a double isolation member, similar to the construction of the right angle members 33 and panels ill, by having a inner formation of plywood (not shown) with opposing sides covered with a shielding material 46, similar to shielding material 16 on panels lid and the shielding material 42 on right angle members 38. Mounted adjacent the edges of the corner member are a plurality of metallic strip members 4-8 so secured to the corner member 44 to permit overlapping onto the panels it? and right angle members Stlwhen mounted in position, as seen in FIG. 6. The corner connector 44 is secured in identical manner as the two panel corner connectlons with plastic inserts being disposed at spaced intervals between the ends of the right angle members 33 and the connecting member 44 and the metallic strip members 48 being secured thereto by screw members 36 and to the plastic inserts by the screw members 34. Thus, it is readily apparent that the only hardware required to assemble the three panel corner junction is the plastic insert member and the screw members, yet the desired continuity of conduction between the adjacent dual shielded panels is maintained since the corner connecting member 44 serves as an electrical isolation unit to maintain the two isolated shielded elements in spaced apart relationship.

One of the primary advantages of this invention resides in the improved and simplified panel construction and the connecting device whereby a highly ethcient isolation room may be made from a single lightweight but solid demountable and interchangeable panel which requires a minimum of connecting hardware to secure the adjacent panels in a tight rigid relationship. The improved construction permits continuous electrical conductive contact between corresponding shield members of adjacent panels to be automatically established as the panels are joined together. The formation and mounting of the strip members on the edges of the prefabricated panels substantially reduces the time of final construction of the room and manufacturing costs. In addition, the utilization of a solid laminated type panel permits the reduction of over all cost without sacrifice of any of the high attenuation efficiency normally required.

Although the preferred embodiment of this invention has been shown and described, it will be understood by those skilled in the art that details of construction may be altered or omitted without departing from the spirit of this invention as defined by the following claims.

What is claimed is:

1. In combination with a prefabricated panel having a dielectric panel member faced on opposite side surfaces With electrically isolated sheets of metal for forming a shielded electrically isolated room, a connecting device for securing adjacent intermediate panels together comprising a dielectric insert disposed between adjacent edge surfaces of the panels, a metallic strip cover member positioned on both sides of the adjacent panels overlapping the insert and said side surfaces marginally along said adjacent edge surfaces and screw members securing the strip cover members to the insert and marginally to the panels to secure the panels in tight rigid relationship and to maintain electrically isolated continuity of electrical conduction between contiguous sheets on opposite sides of the panel members.

2. In combination with prefabricated panel having electrically isolated sheets of metal bonded to opposite side surfaces of a dielectric panel member for forming a double shielded electrically isolated room, a connecting device for securing adjacent panels together in coplanar relation- 7 ship comprising a plurality of dielectric plastic inserts disposed at spaced intervals along and between adjacent edge surface of the panel, a metallic strip member positioned on each of both sides of the adjacent panels to overlap and extend the length of said adjacent edge surfaces, holding screw members positioned centrally through the strip members to engage the inserts, and hold down screws passing through one edge of each strip member and embedded in adjacent panels on opposite side surfaces thereof to secure the panels in tight rigid relationship and maintain continuity of electric conduction between adjacent sheets of metal isolated to the opposite side surfaces respectively.

3. A connecting device for securing three adjacent prefabricated dual electrically isolated shielding panels of an electrically isolated room arranged at right angles and in spaced relation each to the others at their edges, said device including correspondingly shielded right angle members forming corner junctions between pairs of said panels with an open space defined by the adjacent ends of the right angle members, said device comprising a correspondingly shielded connector cover member disposed in said open space, dielectric insert members disposed between adjacent edges of the connector cover member and the right angle members, and metallic strip cover elements bridging and being secured to the insert members and to the adjacent edges of the connector cover member and the right angle members on both sides thereof in a manner overlapping the edges of the connector cover member and the right angle members on both sides in electrically conductive relationship to secure all the panels in tight rigid relationship and to maintain continuity of conduction with contiguous panels isolated to the opposite sides of said members.

4. A connecting device for securing three adjacent prefabricated dual electrically isolated shielding panels arranged in edge spaced relation and at right angles to one another to form a corner of an isolation room, said connecting device comprising a connector cover member disposed in the opening defined by the corner space between the three panels at the corner and having spacing between its edges and the edges of said three panels, a plurality of dielectric insert members disposed at spaced intervals in said spacing between the edges of the connector cover member and the three panels, said cover member having a dielectric portion supporting metal shielding on both its inside and outside surfaces in spaced and electrically isolated relationship, and metallic strip cover members positioned about the peripheral edges on both sides of the connector cover member to bridge said inserts and being secured to the insert members and to the panels in a manner overlapping the edges of the connector cover member and the three panels to secure all the panels in tight rigid relationship and to maintain continuity of isolated conduction between contiguous panels.

5. An electrically isolated room comprising a plurality of unitary panels, each of said panels comprising a dielectric panel member, spaced sheets of solid electrical shielding supported on opposite face surfaces of the panel memher in electrically isolated relationship and securing means to secure adjacent panels in tight rigid relationship including a dielectric insert disposed between adjacent edge surfaces of the panel members and metallic strip members disposed on opposite sides of the panels and bridging the insert, means securing the strip members to the insert in electrically isolated spaced relationship to cover the seam 6 formed between the adjacent edge surfaces of the panel members and provide continuity of electrically conductive contact between adjacent panels and to maintain elec-' trical isolation between the spaced apart sheets of electrical shielding, and means securing one edge of one strip member to one panel and one edge of the other strip member to the other panel to form a double shielded electrically isolated room.

6. In combination with prefabricated panel members and a right angle corner member having thin shielding material secured to both sides of a dielectric material for forming a double shielded electrically isolated room, a connecting device for securing said members together to provide a corner juncture including dielectric inserts disposed in seams formed between the adjacent edges of one of the panel members and the corner member and between the adjacent edges of the other panel member and the corner member, a metallic strip cover member positioned on each of both sides of the panel and corner members at each of said seams respectively and overlapping the seams and inserts in contacting relationship with said shielding material on said respective members, and screw members securing the strip cover members to the inserts and said respective members adjacent the seams to secure them in tight rigid relationship and to maintain continuity of electrical conduction between the shielding material on the same sides of said adjacent panels.

References Cited in the file of this patent UNITED STATES PATENTS 2,066,718 Dietz Jan. 5, 1937 2,405,987 Arnold Aug. 20, 1946 2,838,592 Feketics June 10, 1958 2,860,176 Lindgren Nov. 11, 1958 2,876,275 Schulz Mar. 3, 1959 2,924,638 Feketics Feb. 9, 1960 2,961,478 Burns Nov. 22, 1960 2,978,531 Appleman Apr. 4, 1961 FOREIGN PATENTS 744,723 Great Britain Feb. 15, 1956 

1. IN COMBINATION WITH A PREFABRICATED PANEL HAVING A DIELECTRIC PANEL MEMBER FACED ON OPPOSITE SIDE SURFACES WITH ELECTRICALLY ISOLATED SHEET OF METAL FOR FORMING A SHIELDED ELECTRICALLY ISOLATED ROOM, A CONNECTING DEVICE FOR SECURING ADJACENT INTERMEDIATE PANELS TOGETHER COMPRISING A DIELECTRIC INSERT DISPOSED BETWEEN ADJACENT EDGE SURFACES OF THE PANELS, A METALLIC STRIP COVER MEMBER POSITIONED ON BOTH SIDES OF THE ADJACENT PANELS OVERLAPPING THE INSERT AND SAID SIDE SURFACES MARGINALLY ALONG SAID ADJACENT EDGE SURFACE AND SCREW MEMBERS SECURING THE STRIP COVER MEMBERS TO THE INSERT AND MARGINALLY TO THE PANELS TO SECURE THE PANELS IN TIGHT RIGID RELATIONSHIP AND TO MAINTAIN ELECTRICALLY ISOLATED CONTINUITY OF ELECTRICAL CONDUCTION BETWEEN CONTIGUOUS SHEETS ON OPPOSITE SIDES OF THE PANEL MEMBERS. 